[NCLUG] Linux Partitioning

[adj at ccltd.com]

> > Kind of a newbie question: How can I put 2 parts of the directory structure
> >on one partition and keep the rest on another during an install? I want to
> >put /boot and /var on a small 1GB partition and put the rest on my larger
> >29GB partition but I'm not quite sure how to go about it. Also if anyone
> 
> When it asks what partitions you want, say you want /boot to be 50MB,
> /var to be 1GB-50MB, and / to be 29GB.  If you are talking about
> "discs" instead of "partitions", the installer should allow you to
> specify what discs each partition goes on, simply put /boot and
> /var on one, and / on the other.

But that's 3 partitions.  To get it on two, you'll need to make some
symlinks to make it work.  Or loopback mount stuff.  Short answer is
that 3 /boot and /var on one partition and / on the other isn't going
to work.

Since I'm the sick type (and spent way too much time doing stuff on
HP-UX (ask me about patches, I dare you)), I've done something like
this recently:

    /boot        16 megs, ext2, physical partition
    /            64 megs, ext2, physical partition
    swap	 size of RAM * 2, LVM
    /var         4+ gigs, reiserfs, LVM
    /usr	 2 gigs, reiserfs, LVM
    /tmp         1 gig, reiserfs, LVM
    /home	 8 gigs, reiserfs, LVM

reiserfs on top of LVM is a nice solution because you can pretty
painlessly grow your filesystems.  I've heard that shrinking is a bit
more problematic; haven't tried it myself.  This is probably more work
than anyone really needs to put into partitioning, though.

Oh, and looking at this a bit closer, there's no reason to have
separated / and /boot.  They're easily < 512 megs big.  I think that
happened because it was set up with /boot, swap, and big / with the
installer, then a reiserfs and LVM capable kernel got installed and
stuff was moved around like what you see above.

The LVM stuff comes with a script to make an initrd to use when you'd
like / on LVM, too, but I've opted to go without.  I think 2.4 kernels
don't need that magic to work with / on LVM.

> >knows, could someone explain the difference between the reiserfs
> >and the regular ext2 fs. SuSE offers both on install and I don't
> >know which to use for what.
> 
> /boot has to be ext2, the others can be reiser.  ext2 is more
> stable, reiser doesn't need fscking like ext2 does, so it'll
> probably be a win for you.  Especially on a 30GB disc.  I run reiser
> on my 80GB MP3 disc because I don't want hour+ fsck times.

Actually, reiserfs can be used for /boot as well.  But LILO won't cope
with files with packed tails.  So there's an ioctl() and userspace
utility for unpacking them now (used to be you had to always have the
filesystem mounted with the notails option turned on).  Also / should
not be on reiserfs if reiserfs is a module.  Dunno how SuSE is set up,
but I'd guess they have reiserfs compiled in since they're major
reiserfs sponsors.

Aaron
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